Railway-traffic-controlling apparatus



Patented July .19, 1927'.

LEWIS L. Nn'rTLnroN, onnnenwoon BOROUGH, PENNSYLVANIA, Ass-IGNOR 'ro THE UNION SWITCH & ASIGNAL COMPANY,

ro'RATIoN or PENNSYLVANIA.

F SWISSVALE, PENNSYLVANIA, .A COB- RAILWAY-TRAFFIc-coNrnourNe APPARATUS.

Application am; octpbei- 2a, 192e. y.serial No. 143,378.

*i My invention relates to railwa traic con-y trolling apparatus, and particu arly to a'p- 'paratus of the type involvin` train-carried 0roverning mechanism control ed'inductively y current flowing in the track rails.' 1 One feature of my invention isthe provision lof means for'giving three nnlications' on the traingwith a lsingleatrackway circuit for each' section yand a single train-carried receiver. .p

I' will describe one form of' apparatus embodying my invention, and will then "point out the novell features thereof inI claims.

a diagrammatic -viewshowing one forni of lapparatus embodying my invention.y l Fig. 2

1s a. groupA of curves illustratingy the operation'of theapparatus shown in Fig. l.. Fig.'- 3 is a curve showing the characteristics of the electrontubes forming part `of the apparatus shown in Fig. |1

Altefer'ring'first to Flg, l, thel reference i .characters 1 and .1 designate the trackra-il's vof a stretch of railwaytrackl along which `trailic normally moves in the direction indicated lb l by insu ated joints 2 into a plurality of sec. tions of `which only twol complete sections A-#Band B-C are shown in the drawing. As here shown, each section .isv provided .with

av .signal S located ,atthe ventrance end lof "the section and arranged to indicate` proceed,

caution or stop. Inasmuchas the controlw'of these signals hasv nothing y to do with.l my' present invention II have omitted the controlling apparatus from the ,drawing to simplifyA the disclosure.

sigirlials may-beomitt'ed, if desired.

ach 'section is Aprovided with a` source of' direct current, which, as here shown, is

a .battery,D, and this battery. is connected with the track rails radjacent the exit tend 'of the section vthrough l.a pole-changer PA fwhic'h is` operated by thesignaljS forthe next section in advanceinl such manner that the pole-changer is in its normal position when the signal indicatesproceed or c'autlon, and in itsl reverse position when the slgnal indicates stop..A Interposed betweeny each- -pole-changer P and one track rall''is an 1x1-I terrupt'er'I, which, inthe form here shown, is a commutator 'constantly operated by a motor M which in turn 1s energized from the adjacent battery D.l The commutator I therefore, that the two coils the arrow.V These railsare divided- Furthermore, the Y lis preferably so` arranged that the period during which current is supplied -to the lthe track rail la.

. Located to the right. of point C, isa trai-n 1 -or vehicle represented by apair of wheels 5 transversely disposed above the track rail l y 1 and a corera transversely disposed above In the laccompanying drawing, Fig. 1.1s.v

the'track rail 1a. The core 5 carries a coil coils are` connected in series in a receiving circuit Lin 'such manner' that 'thevoltages created inthe two coilsby current flowing in opposite directions a glvenjnstant are additive.' It will be seen,

`6 yand y6a consti- The interrupter I l and an axle/V, Located .in front of thefor-` i ward wheels land axle of this train is a core the track rails at` tute a Winding which receives voltage'inductively from the track rails. lalso carries a normal electron tube E1 and a reverse electron" tube'E`2,'each of which tubes is of the three-'element type'havin'g a fila- The vehicle V ment, -a` grid and a plate. The l.filament of each -tube is constantly heated b a battery l` f 12. Thegrid circuits ofI the tu es El and;

Ezvare reversely connected with the receiving circuit AL, that is, the filament of tube E1 is 'connected with the upper terminal of coil 6 and the grid of this tube is connected with the lower terminal of coil-6, whereas the filament. ofv tube. E2 is connected with the 'lower terminal of coil 6 and the lgrid of tube E2 `is connected with the upper terminal j of coi16. f-The grid of each tube is main-v tained negative l with respect tothe filament of the,A same -tube by a batteryy 1.3. Tube E1 i'sprovided with a plate circuit includ-ing a winding 14 .'of a relay R and a plate battery f 10. 4Tube E2 is provided 'with a plate .cirp cuit, 'including a winding 7 of relay R and av plate battery' 10. The relay R comprises anarmature 9,` whichis shifted tothe right into engagement with fixed contact gazwhen .winding 14 is energized,and to the left'into engagementwithflixed contact 9?"when wind.

ing'i' is energized. The.y relay Rmaylcon- V' trol train governing mechanism of anyvsuitable type, which mechanism, as here shown, isa cab 'signal S1, lia-ving a high speed lamp 8H, a medium speed lamp 8 1, and astop lamp 8S. The circuits for these lamps obvious from the drawing, from which 1t 1s seen that each lamp is supplied withcurrent trom a suitable source the terminals of which are indicated by the reference characters K and O.

The operation of the apparatus showii in Fig. 1, is illustrated by the curves constitutclosed for relatively long intervals X, and

ing Figs.'2fand. 3'. In Fig. 2, the curve F illustrates the operation of the interrupter I, and from this curve it will be noted that, as stated hereinbefore, the interrupter is open for relatively short intervals Y. The

current in the track rails is indicated in curve G, the solid-lines in this portion of Fig. 2 showing the -current when the "polechanger P is in normal position and the dash lines showing the current when the polechanger is in the reverse position;l Due to .the reactor 4 and to the inherent reactance o1 the track rails, the time constant of the track circuit is such that during `each period X th'e current builds up slowly, as indicated at a, while vduring-each period Y the current dies out quickly, as shown by the portion b of the current curve. When thel polechanger'P is in the reverse position, the two` portions of the current curve are as illustrated bythe part-s a:1 and bl. The condenser 3 across the interrupter serves both 'to reduce sparking Aat the interrupter contacts and also to increase the steepness of the portions b and b1 of the current curves. Curve H shows the wave form of the voltage. inducted in the receiving circuit L onthe train. When the pole-changer is in the normal position, the voltage has a positive peak dwhich is relatively high', and a negative peak c which is relatively low. When' the pole-changer Pis in the reverse position, the

curve has a negative peak d'1' which is rela'.-

tively high and a positive peak cwhich'is,

relatively low.

Fig. 3 shows the characteristic curve of each electron tube E1 and E2. From this curve it will be noted that due to the negative bias created by the battery 13, aconsiderable grid voltage is required to overcome this bias. Tube E1 is so connected with thel receiving circuit that it will respond to the normal voltage, that is, to the voltage indicated by the solid line in curve H o Fig.

2, whereas tube E2 is so connected to the rel ceiving circuit that it will respond only to whereas pole-changer P for section lB--C is in the normal position. It follows that when the vehicle V. enters section B-C, relay R will continue to be lener ized in the normal direction so that the high speed lamp 8H will continue to be lighted, but that when the vehicle enters section A-l-B the ener ation of .relay R will bev reversed, so t at the medium speed lampM will become lighted.

,for sect-ion A-B is in the reverse position,

Of course, when the vehicle enters an occupied section or when for any other reason the supply of energy from the track rails is discontinued, armature 9 of relay R will assume its intermediate position wherein the stop lamp 8S will be lighted.

Although I have herein shown and ,described only one form of apparatus embodying my invention,l it is understood that various changes and modifications may be made therein within the scopevof the appended claims without departing from the spirit and scope of my invention.

Having thusv described my invention, what I claim is 1. In. combination, a section of 4railway versely connected with said receiving circ uit, two coils supplied with energy by the plate circuits of said two tubes respectively,

and governing mechanism on the train controlled by Said two coils.

2. In combination, a sect-ion of railway track, a source of direct current reversibly connectedwith the rails of said section, means for periodically interrupting the supply of current from said source to the track rails, a train carried circuit receiving energy inductively from the track rails, two electron tubes having their grid circuits reversely connected with said receiving circuit, means or creating a negative bias on the 'grid of each tube, twov coils supplied with energy by the plate circuits of said two tubes respectively and governing mechanism on the train controlled by said two coils.

. .3.' In combination, "afsectionfof"railway track, a source of direct"currentfconnected with the rails of said section, -a-pole-changer interposed between said jsource 'andqsaid rails, an interrupter interposed between said pole-changer andone rail, a .train carriedy circuit receiving energy inductively from the trackv rails,` .two electron tubes having their grid circuits re'versely connected withvsaid receiving'vcircuit, two `coils'supplied'l with en-` l. ergy by the plate circuits of said twotubes respectively, and governing mechanism on the train controlled by saidftwocoils.

4. In combination,l a'section of railway track, a source of direct current connected with the rails of said section, a pole-changer interposed between said sourcey and "said ra'ils, an interrupter interposed between said pole-changer andone rail, a condenser connected in multiple withl said interrupter, a

-, train carriedcircuit receiving energy induc-` tively fromthe track rails, two 'electrontubes f having their grid circuits reversely connect ed with said receiving-circuit, two coils supplied with energy by theplate circuits of .said l two tubes'r'espectively, and governing mechanisni -on the 'train fcoiitrolled-by said two v tube, two coils supplied 'with energy by thel coils. f

5. In combination,u a section of railway track, a. source Iof direct currentV connected with the rails of said section, appele-changer Vinterposed between said source. and said rails, an interrupter interposed between said pole-changer and one rail, a cpnd'enser con-y nect'ed in multiple with said interrupter-a train carried circuit receiving energy inductively-from theztrack rails, two electron tubes having their grid circuits -reversely `connected with said receiving circuit',means fory creating a`negative bias on the grid of each plate circuitsfof said two tubes respectively,

and rgoverning 6. In combination, fa 'section ot'V railway track, a source of direct currentconnectedl with? the rails 'of said section, a pole-changer interposed between, said` sourceand said ceiving `energy inductively from the track.

rails, an interrupterinterposed between said pole-changer andfone rail, a'reactorinterposed vbetween said pole-changer and `one rail` la condenser connected infmultiple with said interrupter, a. train `carried circuit re- Way, two electron tubes having tlieirgrid circuits reversely connected with said receiving circuit, means `foijcreating a .negative 'bias'on tlie grid-.of each'tube, two coils sup-1 Q -pl-ied with energy bythe plate'circuits of said two tubes respectively, and governing mechanism on the train-controlled vby'said two coils. c

.7. ,In combination, a section of railway track, a source of direct'current connected with the rails of said section, apole-changer .trolled .by -said two coils. mechanism on the train coninterposed between said source and said rails, an interrupter inter osed between said. pole-changer and one'rail), be' closed for relatively long periods and. open for relatively short periods, a condenser A connected in multiple lwith lsaid interand arranged to i connected with therails of said section, i

means for periodically interrupting'the supply of current 4from said source to 'said' rails in such'4 manner that the periodsot supply lare relatively longandfthe periods of interruption are relatively short, a train carried .circuit receiving energy inductively from the track rails, two,v electron 'tubes having their- -grid circuits revei'sely connected with said -receiving circuit, two coils supplied with energy by the plate circuitsof said' two tubes respectively, and governing mechanism on the,traiir controlled by' said twocoils.

9. In combination, a section/of Arailway track, means yfor reversib'lyapplying to the rails ofsaid section a periodic current each wave of which builds up slowly A,from zero to maximum and dies away quickly from 1naxi.

mum to zero, a train carried .circuit receiving lenergy inductively from the vtrack rails, two electron tubes having their grid circuitsy 'reversely connected with said receiving -circuit, two coils supplied with energy by thek platecircuits of said two tubes respectively,

and governing" mechanism on the train con- .10. In combination, a section of railway .track,-iiieans for reversibly applying tothe f 110 rails of 'said' section a periodic current veach wave oi which builds up slowly from zeio to maximumand dies awayquickly from maximum to zero, a train carried circuit re- Y' rails, two electron tubes lhaving their grid circuits -reversely connected with said re-A ceiving circuit, means for creating-a.negav tive, bias on the grid of each tube,two coils supplied with energy by the plate circuits' of said two, tubesrespectively, and governingy mechanism on the 4train controlled by said twocoils. v V 1 f Y 11. Incombination,a` section ofrailway Atrac means for reversibly -ap'plying'to the rail fof s aid .section aperiodic-current each wavevofwhichbuilds ups'lowly from zero to gmaximum and dies Vaway quicklyl from vmaximum to zero, a train carried winding receiving voltage inductively from said track rails, a normal electron tube'having its lilalceiving energy inductively from the track iso Y ment connected with one terminal of said winding and its, grid connected 'with theother terminal of said winding, a reverse electron tube having its-grid connected with the first terminal of said winding and its filament vconnected with the second terminal,

means for keeping the grid of `each tube negative with respectto the filament of the same tube, two coils supplied with energy by the plate circuits of said two tubes respectively, and governing mechanism on the train controlled by said two coils'.

12. In combination, a section of railway track, means for supplying to the rails of said section a current which fiuctuates periodically and which changes rapidly in a first direction and slowly in a seconddirection, means for reversing the conditions so that the current changes slowly in the first direction and rapidly in the second direction, and governing mechanism on a train selectively responsive tothe two said conditions under which said current is supplied to' the rails. 1

13. Iny combination, a section` of `railway track, means' for supplying to the rails of.

said section a current which fluctuates periodically and which changes rapidlyv in a first direction and slowly in a second direction, means for reversing the conditions so that the current changes slowly in the first direction and ra idly in the second direction, a train carrie circuit receiving energy induetively from the track rails, two e'lectron tubes' having `their grid circuits reversely connected with said receiving circuit, two coils supplied with energy by the plate circuits ofsaid-two tubes respectively, and governingymechanism on the train controlled by i said two coils.

14. In combination,'a section of rai'lway track, means for supplying to the rails of. said section a current which fiuctuates peri'- odically and which changes rapidly in a first direction and slowly in a second direction, means for reversing the conditionsv so that the current changes 'slowly inthe first direction and rapidly in the second direction, atrain carriedcircuit receiving energy inductive'ly from the track rails, two electron tubes havin their grid circuits reversely connected w1th said receiving circuit, means for creating a negative bias on the grid of each tube, two coils supplied with energy by the plate circuits of said two tubes respective and governing mechanism on the train controlled by said two coils.

1-5. In' combination, a section of railway i track, means 'for supplying" to the rai'ls ofA said' section a current which fluctuates periodically and which changes rapidly in a first direction andslowly in a second direction,

means for reversing the conditions so that the current changes slowly in the first direcu .tionand rapidly in the second direction, a train carried lwlnding receivin voltage in ductirely from said track rai s, a normal electron tub.; `having vits filament connected with one terminal of saidwinding andV its grid connected with the other terminal of said winding, a reverse electron tube having its grid connected with the first terminal of said winding andits filament connected with A the second terminal, means for keeping the grid of ,each tube negative with respect to vthe ilamentof the same tube, two coils sup- .plied with energy. by the plate circuits of said two tubes respectively, and governing mechanism on the train controlled by said two coils. l i

In testimony whereof I affix my signature.

v LEWIS L. NETTLETON. 

